I duly adjusted the picture in my mind. Now I imagined a friendly stallion galloping wildly across the plains.

"What kind of nice horse?" I probed.

"A gelding," he pronounced.

A castrated horse! That was unexpected. The picture in my mind changed completely.

Now I envisioned my father as a gentle dray horse, docilely pulling a cart driven by my mother.

"Why a gelding?" I asked.

"I've found that life is just easier that way," he replied. "Trust me."

And so life has been easier for him. In exchange for the almost castrating constraints that marriage has clamped on my father's personal freedoms, he has received stability, prosperity, encouragement in his labors, clean and mended shirts that appear as if by magic in his dresser drawers, a reliable meal at the end of a good day's work. In return, he has worked for my mother, he has been faithful to her, and he submits to her will a solid 95 percent of the time--elbowing her away only when she comes a little bit too close to achieving total world domination. The terms of this contract must be acceptable to both of them because--as my mother reminded me when I phoned her from Laos--their marriage now endures into its fifth decade.

The terms of my parents' marriage are probably not for me, of course. Whereas my grandmother was a traditional farmwife and my mother was a feminist cusper, I grew up with completely new ideas about the institutions of marriage and family. The relationship I'm likely to build with Felipe is something my sister and I have termed "Wifeless Marriage"--which is to say that nobody in our household will play (or play exclusively) the traditional role of the wife. The more thankless chores that have always fallen on women's shoulders will be balanced out more evenly. And since there will be no babies, you could also call it "Motherless Marriage" I suppose--a model of marriage that my grandmother and mother obviously never experienced. Similarly, the responsibility of breadwinning will not fall entirely on Felipe's shoulders, as it fell to my father and grandfather; indeed, the bulk of the household earnings will probably always be mine.

Perhaps in that regard, then, we will have something like a "Husbandless Marriage" as well. Wifeless, childless, husbandless marriages . . . there haven't been a whole lot of those unions in history, so we don't really have a template to work with here. Felipe and I will have to make up the rules and boundaries of our story as we go along.

I don't know, though. Maybe everyone has to make up the rules and boundaries of their story as they go along.

Anyway, when I asked my mother that night on the phone from Laos whether she has been happy in her marriage over the years, she assured me that she'd had a really nice time of it with my father, far more often than not. When I asked her what the happiest period of her life had been, she replied: "Right now. Living with your dad, healthy, financially stable, free. Your father and I pass our days doing our own thing and then we meet at the dinner table together every night. Even after all these years, we still sit there for hours talking and laughing. It's really lovely."

"That's wonderful," I said.

There was a pause.

"Can I say something that I hope doesn't offend you?" she ventured.

"Go for it."

"To be perfectly honest, the best part of my life began as soon as you kids grew up and left the house."